Ultramulsion containing interdental delivery devices

ABSTRACT

The present invention relates to unique interdental delivery devices, other than dental floss, which are suitable for cleaning, massaging, and/or treating surfaces of teeth and gums including interproximal and subgingival areas; wherein these devices contain ULTRAMULSION™ dispersions of high viscosity silicones dispersed in surfactants, these dispersions are released into the oral cavity from these devices during use wherein the dispersed silicone: 
     a. is insoluble in the surfactant and oriented so as to form coatings in the oral cavity with enhanced substantivity, 
     b. functions as a reservoir for various lipid soluble and/or liquid dispersible ingredients to be released onto oral cavity surfaces, and 
     c. has a particle size from between about 0.1 and about 10 microns with from between about 80% and about 95% of the particles within this range.

BACKGROUND OF THE INVENTION

The present invention relates to unique interdental delivery devices,other than dental floss, which are suitable for cleaning, massagingand/or treating surfaces of teeth and gums including interproximal andsubgingival areas, containing a dispersion of certain silicones incertain surfactants. When added to water these dispersions are stableand are distinct from solutions, emulsions and microemulsions. Thesedispersions are referred to hereinafter as ULTRAMULSION™ dispersions.This trademark is the property of Whitehill Oral Technologies, Inc. Forfurther information regarding ULTRAMULSION™ dispersions, see copendingapplication Ser. No. 08/144,778, now U.S. Pat. No. 5,538,667, thedisclosure of which is hereby incorporated herein by reference. See alsocopending patent application Ser. Nos. 08/462,613; 08/462,203;08/462,600; 08/463,010; 08/461,698; 08/464,403; and 08/462,930; allfiled on Jun. 5, 1996, the disclosures of which are hereby incorporatedby reference.

The interdental devices of the present invention include interdentalstimulators, massagers, and the like, including elastomeric massagersand wooden sticks, typically from about 5-10 cm long, tapered at one orboth ends with cross sectional dimensions from between about 0.5 mm andabout 5 mm. Elastomeric, rubber type massagers such as those attached tospecial handles or the end of toothbrushes are of particular use for thepurposes of the present invention.

The interdental devices of the present invention contain ULTRAMULSION™dispersions at from between about 1% and about 50% by weight of thedevice. Preferably these devices are wooden (balsa or bass wood arepreferred) or composed of an elastomeric substance with someflexibility. All the devices provide various passageways, voids etc.suitable for loading ULTRAMULSION™ dispersions that can be releasedduring cleaning, massaging or treating of surfaces in the oral cavity.

The interdental stimulators and massagers of the invention do notrequire the dexterity required by dental floss. Wolffe, G. N., J. ofClinical Periodontal, 3:145-156 (1976) reported 51.4% of subjects testedpreferred interdental stimulators vs. 11.5% preferring dental floss. Ifperiodontal disease is to be controlled, then the accumulation of plaquearound the gingival margins of the teeth and also on proximal surfacesmust be prevented. Ibid.

The ULTRAMULSION™ dispersions released from the interdental deliverydevices of the present invention exhibit unique and unexpectedsubstantivity to oral surfaces including teeth and gums while providinga reservoir for various lipid soluble and/or lipid dispersible activeingredients resulting in antiplaque, antibacterial, antigingivitiscleaning and treating benefits that last for extended periods. Thiscombination of enhanced substantivity and the reservoir effect describedin detail below are further combined with excellent particle size toprovide optimum treatment coatings to the interproximal and subgingivalareas of the mouth when released from the interdental delivery devicesof the present invention.

Other oral care products containing the ULTRAMULSION™ dispersions of thepresent invention include: rinses, spray, gels, creams, toothpastes,tooth powders, denture cleaning tablets, dental floss, mints, andchewing gums as described and claimed in copending patent applicationsreferenced above.

The interdental delivery devices of the present invention may be used bydentists and hygienists in various professional oral hygiene treatmentsand/or may be used by consumers for various at-home and away-from-hometreatments ranging from massaging and cleaning to antiplaque,anti-gingivitis and anti-tartar hypersensitivity treatment,remineralizing, whitening, stain removal, and the like.

As to Antiplaque Benefits:

The present invention further relates to the interference with theformation of plaque. Plaque is a microbial coating on tooth surfaces,bound together by natural polymers (e.g., mucopolysaccharides) formed bymicrobial action on the cell debris, food remnants, sugars and starchesin the mouth. Embedded in this polymer matrix are the bacteria normal tothe oral cavity but, when trapped against tooth surfaces and protectedby the matrix from easy removal, are in excellent position for"mischief." Most dental texts implicate plaque in the formation ofcaries, or tooth decay. In addition, these embedded bacteria releasetoxins that cause gingivitis, bleeding and swelling of the gums.Gingivitis can lead to periodontitis in which gums recede, pockets ofinfection form and teeth loosen.

Plaque formation is an ongoing process. Various gel and paste dentifricepreparations, mouth rinse and mouth pre-rinse preparations make plaqueand/or tartar control claims. One disadvantage of these preparations isthat only a relatively short time during which the teeth are beingcleaned or the mouth is being rinsed is available for these preparationsto take effect. These preparations generally have little residual effecton plaque formation. Additionally, some of these preparations such asmouth rinses and pre-rinses contain various antimicrobial substanceswhich may alter the critically balanced microflora of the mouth. Anotherdisadvantage of these preparations is the general infrequency of use.That is, most are used once or perhaps twice daily and seldom when theyare most needed, e.g., after meals, snacks, smoking, drinking, coffeebreaks, etc.

The ULTRAMULSION™ dispersion containing interdental devices of thepresent invention are particularly effective at removing plaquemechanical cleaning while simultaneously helping to fight plaque buildupand/or treat gingivitis by releasing some of the ULTRAMULSION™dispersion onto the area being treated. The role of controllingsupragingival plaque in the prevention and treatment of periodontaldisease is reviewed by Korman K. S. Journal of Periodontal ResearchSupplement. 5-22 (1986).

According to Bass C. C. in Dent. Items of Interest, 70:921-34, (1948)there is " . . . considerable area on proximal surfaces of teeth, whichcannot be reached by the bristles of the toothbrush." The efficacy ofwooden interdental stimulators (J & J STIM-U-DENTS®) vs. Peridex™ Rinseis detailed by Mankodi et al., J. of Dental Res. Special Issue, 246(1988). "The greatest incidence and severity of inflammatory periodontaldisease has been reported in the interproximal area." Ibid.

Wooden interdental stimulators which are round or rectangular in crosssection remove plaque from the bowel part of the proximal surfaces,whereas triangular interdental stimulators are effective on both buccaland lingual parts of proximal surfaces according to Bergenholtz et al.,J. of Clinical Perio. Res., 1:160-165 (1974).

Effective oral hygiene requires that three control elements bemaintained by the individual:

1. Physical removal of stains, plaque and tartar. This is accomplishedin the strongest sense by scraping and abrasion in the dentist's office.Self administered procedures are required frequently between visits andrange from tooth brushing with an appropriate abrasive toothpastethrough flossing and water jet action down to certain abrasive foods andeven the action of the tongue against tooth surfaces.

2. Surfactant Cleansing. This is required to remove: food debris andstaining substances before they adhere to the tooth surfaces; normaldead cellular (epithelial) material which is continually sloughed offfrom the surfaces of the oral cavity and microbial degradation productsderived from all of the above. Besides the obvious hygienic and healthbenefits related to simple cleanliness provided by surfactants, there isan important cosmetic and sense-of-well-being benefit provided bysurfactant cleansing. Research has shown that the primary source of badbreath is the retention and subsequent degradation of dead cellularmaterial sloughed off continuously by the normal, healthy mouth.

3. Frequency of Cleansing. This is perhaps the most difficult to providein today's fast-paced work and social environment. Most people recognizethat their teeth should be brushed at least 3 times a day plus aftereach snacking occasion.

The simple fact is that most of the population brush once a day, somebrush morning and evening, but precious few carry toothbrush anddentifrice to use the other three or four times a day for optimal oralhygiene. Consumer research suggests that the population brushes anaverage of 1.2 times a day. Thus, the 24 hour period between brushingsfor a majority of the population provides optimum plaque formingconditions with no interruptions.

Since plaque is regarded by most of the dental profession as a causativeagent leading to various dental pathologies as noted above, there isconsiderable desire by most consumers to disrupt or prevent theformation of plaque on a daily basis. There are three oral carestrategies which address the problem of plaque: abrasion, anti-microbialagents and removal of precursors to plaque.

1. Abrasive removal of the plaque film, once it has firmly adhered tothe tooth surface, is the only totally effective cleansing mechanism.Again, professional dental hygiene is the most effective, but recently anumber of special abrasive toothpastes have been accepted by dentalorganizations as partially removing adhered plaque and the tartar whichsubsequently forms from the plaque.

2. Antimicrobial action could affect plaque formation in two ways, (a)reducing the number of bacteria in the mouth which form themucopolysaccharides and (b) killing those bacteria trapped in the filmto prevent further growth and metabolism. However, the medical anddental community is divided about the advisability of frequent use ofantimicrobial agents in the mouth in rinses or pre-rinses, especiallythe most effective ones, except under strict supervision of licensedpractitioners. There are a number of reasons given, but one concern isthat such materials would upset the ecological balance of the mouth. Abalanced, "friendly" microbial population is necessary to preventpathogenic organisms from taking over.

3. Removal of plaque precursors requires the reduction of food sourcesand building blocks required for the bacteria to synthesize themucopolysaccharides which polymerize into the plaque film. Going farback into the chain of events leading to plaque formation andinterrupting the chain has much to commend it as a sound oral hygienestrategy. However, for this strategy to be effective, the plaquebuilding blocks must be interrupted periodically. As noted above,heretofore, the oral hygiene preparations described above fall short on"frequency-of-use" basis.

For reference see: L. Menaker, The Biologic Basis of Dental Caries,Chapters 5, 11, 12, 14, 16 and 18, Harper & Row (1980). See also U.S.Pat. Nos. 4,465,661; 3,507,955; 4,902,497; 4,661,341; 4,666,708;4,537,778; 4,657,758; 3,624,120; 4,525,342; 4,476,107; 5,078,988;2,806,814; 4,774,077; 4,612,191; 4,353,890; 4,894,220; British Pat. No.689,679, Gatter et al., Journal of Pharmaceutical Sciences, 74:1228-1232(1985); and Bass, Dent. Items of Interest, 70:21-34 (1948).

As to Antitartar Benefits:

Dental calculus, or tartar as it is sometimes called, is a deposit whichforms on the surfaces of the teeth at the gingival margin. Supragingivalcalculus appears principally in the areas near the orifices of thesalivary ducts; e.g., on the lingual surfaces of the lower anteriorteeth and on the buccal surfaces of the upper first and second molars,and on the distal surfaces of the posterior molars.

Mature calculus consists of an inorganic portion which is largelycalcium phosphate arranged in a hydroxyapatite crystal lattice structuresimilar to bone, enamel and dentine. An organic portion is also presentand consists of desquamated epithelial cells, leukocytes, salivarysediment, food debris and various types of microorganisms.

As the mature calculus develops, it becomes visibly white or yellowishin color unless stained or discolored by some extraneous agent. Inaddition to being unsightly and undesirable from an aestheticstandpoint, the mature calculus deposits are regarded by many as aconstant source of mechanical irritation of the gingiva.

A wide variety of chemical and biological agents have been suggested inthe art to retard calculus formation or to remove calculus after it isformed.

Mechanical removal of this material periodically by the dentist is, ofcourse, routine dental office procedure.

The chemical approach to calculus inhibition generally involveschelation of calcium ion and/or crystal growth inhibition which preventsthe calculus from forming and/or breaks down mature calculus by removingcalcium.

The prior art discloses a number of chelating agents for this purpose.British Pat. No. 490,384, Feb. 15, 1937, discloses oral compositionscontaining ethylenediaminetetraacetic acid, nitrilotriacetic acid andrelated compounds as anticalculus agents. U.S. Pat. No. 3,678,154, Jul.18, 1972 to Widder et al. discloses oral compositions containing certainpolyphosphonates and fluoride.

U.S. Pat. No. 3,737,533, Jun. 5, 1973 to Francis discloses oralcompositions containing certain carbonyl diphosphonates. In addition tothe above references, the prior art discloses dentifrices andmouthwashes containing soluble pyrophosphate salts which have beenincluded for a variety of purposes. Included among such references areU.S. Pat. No. 2,941,926, Jun. 21, 1960 to Salzmann et al. whichdiscloses dental powders containing chlorophyll and pyrophosphate salts.U.S. Pat. No. 3,137,632, Jun. 16, 1964 to Schiraldi disclosestoothpastes containing pyrophosphate salts. U.S. Pat. Nos. 3,927,201 and202, Dec. 16, 1975 to Baines et al. and Harvey et al., respectively,disclose toothpastes which utilize soluble pyrophosphates as abrasives.U.S. Pat. Nos. 4,244,931, Jan. 13, 1981 and 4,247,526, Jan. 27, 1981 toJarvis et al. disclose pyrophosphate salts in dicalcium phosphatesystems. Jap. Patent Application Disclosure No. 4945-1974 disclosessoluble pyrophosphates in a variety of dentifrice systems. U.S. Pat. No.4,333,551, Apr. 6, 1982 to Parran discloses tetralkali metal salts inmouthwash compositions.

In addition to the use of the above mentioned materials the use ofcertain acrylic acid polymers and other agents have also been disclosedfor use as anticalculus agents. Included among such agents arepolyelectrolytes such as copolymers of maleic anhydride and ethylenedisclosed in U.S. Pat. No. 3,429,963, Feb. 25, 1969 to Shedlovsky.Shedlovsky also discloses polyacrylic acid having an average molecularweight of 1500 and greater. Other references disclosing polyacrylicacids in oral compositions are South African Pat. No. 720898, Sept. 12,1972 which discloses such acids having a molecular weight of from 1000to 2,000,000; and U.S. Pat. No. 4,304,766, Dec. 8, 1971 to Changdiscloses polyacrylic acid having a molecular weight in the range of2,000 to 4,000,000 for use as a membrane to prevent the elution fromteeth of previously applied agents. Finally U.S. Pat. No. 3,956,480, May11, 1976 discloses complexes of anionic polymers (e.g., acrylic acid)and a cationic therapeutic agent (e.g., chlorhexidine) as anticalculusagents.

As to Anti-Gingivitis Benefits:

It is generally accepted that antimicrobial substances are mosteffective in responding to gingivitis flare ups/infections of the gums.Suitable antimicrobials include stannous fluoride, as described in: U.S.Pat. Nos. 5,057,308; 5,057,309; 5,057,310 and in the FDA filingresponsive to the Sep. 19, 1990 call-for-data (55 Fed. Reg. 38560) filedby WhiteHill Oral Technologies Jun. 17, 1991, Docket 81 N-0033, OTC210246 to 210262 and 210339 and specifically the "Annotated Bibliographyset out in Vol. VI of said filing.

Other anti-gingivitis antimicrobials include chlorhexidine, halogenateddiphenyl ethers such as triclosan, phenol and its homologs and theessential oils used in Listerine®. U.S. Pat. Nos. 4,022,880 and4,894,220 disclose and claim various triclosan based oral care products.U.S. Pat. No. 4,894,220 includes an extensive teaching on phenol and itshomologs suitable as antimicrobial agents. Metronidazole is discussed indetail in U.S. Pat. No. 4,568,535. The Listerine® essential oils aredescribed in detail by Kornman in Journal of Periodontal Research,Supplement 1986:5-22 (1986).

Other anti-plaque active ingredients include:

a. Quaternary ammonium compounds including benzethonium chloride,cetylpyridinium chloride as described by Volpe et al., Journal of DentalResearch, 48:832-841 (1969) and Gjermo et al., Journal of PeriodontalResearch, 5:102-109 (1970).

b. Phenolic compounds including the mixture of thymol, eucalyptol,menthol along with methyl salicylate described as "essentials oils" inListerine®. See Fornell et al., Scandinavian Journal of Dental Research,83:18-25 (1975), Lusk et al., Journal of the American Society ofPreventive Dentistry, 4:31-37 (1974); Gomer et al., Journal of theAmerican Society of Preventive Dentistry, 2:12-14 (1972).

The ULTRAMULSION™ dispersion containing interdental delivery devices ofthe invention are particularly effective at delivering therapeuticagents, interproximally, subgingivally and into certain periodontalpockets. A portion of the ULTRAMULSION™ dispersion containing thetherapeutic agent is released during picking or massaging of the areabeing treated by the device. The released ULTRAMULSION™ dispersionthereby provides continuous therapy for the site being treated.

Therapeutic delivery devices suitable for treating periodontal pocketsare described and claimed in U.S. Pat. Nos. 4,764,377 and 4,892,736.Impregnated and treated dental stimulators are disclosed in U.S. Pat.No. 4,942,034.

Oral therapeutic delivery devices are also discussed in: Goodson et al.,J. Periodontal., 54:575-579 (1983); U.S. Pat. Nos. 3,674,901; 3,849,185;4,042,871; and Goodson J. M. Medical Applications of Controlled Release,Vol. II, Chapter 7, CRC Press, Boca Raton 115-138 (1984); Bergenholtz etal., J. Clin. Periodontal, 1:160-165 (1974); Addy et al., Journal ofClinical Periodontology, 11:467-474, (1984); and Golomb et al., Journalof Dental Res., 63:1149-1153 (1984).

As to Periodontitis Benefits:

The main cause of tooth loss in adults is periodontal disease. Yet,surprisingly, less than one percent of the public expenditures fordental treatment is for periodontal disease (see J. Dent. Educ., 43:320(1979). This is because conventional periodontal treatment is tooexpensive for most individuals, mainly due to the labor intensive,symptomatic treatment that is usually performed by highly skilledspecialists.

Periodontal disease is an all-inclusive term for a variety of clinicalentities that are forms of either gingivitis or periodontitis.Gingivitis is an inflammation of the gingiva or gums that can beassociated with poor oral hygiene and/or hormonal states of the host. Itis assumed, but not proven in the human, that gingivitis will progressto periodontitis, which is the form of the disease in which theinfection has progressed to involve the oral tissues which retain theteeth in the jaw bone. Periodontitis is the more severe form of thedisease, and if untreated, will eventuate in the loss of the tooth.

Dentists have long assumed that periodontal disease originates by theovergrowth of bacteria on the tooth surfaces in aggregates known asdental plaque. If this plaque persists for long periods of time on thetooth surfaces, it may in some instances calcify, forming the hardsubstance known as calculus. Numerous studies describe chemical agentswhich can in vitro and in vivo reduce plaque formation and calculus.However, none of these chemical agents has been reported to besuccessful in treating periodontitis.

A substantial number of different types of compounds and compositionshave been developed for use as antibacterial and antiplaque agents,e.g., benzethonium chloride and cetyl pyridinium chloride, disclosed inU.S. Pat. No. 4,110,429, or as anticalculus agents, e.g.,2-phosphono-butane 1,2,4-tricarboxylic acid, disclosed in U.S. Pat. No.4,224,308. These compounds are designed to be used by the individual indentifrices, dental powders, pastes, mouthwashes, nonabrasive gels,chewing gums, topical solutions and the like, e.g., see U.S. Pat. No.4,205,061. They are designed to be used as prophylactic agents, usuallywithout requiring a prescription or supervision during usage, e.g., seeU.S. Pat. No. 4,251,507. Often they are compounded with detergents andother cleaning agents, and this cleaning action is often an importantaspect of the invention, e.g., see U.S. Pat. Nos. 4,251,507 and4,205,061. None of these compounds or compositions are designed to beused as antimicrobial agents for the treatment of periodontitis, nor arethey formulated to be slow release devices for these antimicrobialagents in vivo.

Recent research in periodontal disease (see, for example, Chemotherapyof Dental Plaque Infections, Oral Sci. Rev., 9:65-107 (1976) indicatesthat gingivitis and periodontitis are characterized by different typesof bacteria. Gingivitis is associated with the accumulation of Grampositive cocci and actinomyces, whereas periodontitis is characterizedby proportional increases in anaerobic bacteria, such as spirochetes andblack pigmented bacteroides (see "Host-Parasite Interactions inPeriodontal Disease," R. J. Genco and S. E. Mergenhagen, ads., Amer.Soc. for Microbiol. Washington, D.C. p. 27-45, 62-75, 1982). Thedifferent bacterial compositions of plaque associated with eithergingivitis or periodontitis suggest that a mode of treatment that iseffective in gingivitis may not be effective in periodontitis. Previousdiscoveries in the area of periodontal disease have assumed that thereis no bacterial specificity in periodontal disease. This is now known tobe incorrect. These bacterial difference in plaque may explain why anagent effective in plaque control, such as chlorhexidine, has littleeffect on gingivitis and no published effect on periodontitis.

Another important finding from recent periodontal research is that thecomposition of the dental plaque will differ according to its locationon the tooth surface. Above the gingival or gum margin, facultativebacteria, such as Gram positive cocci and rods, are numericallydominant, whereas below the gum margin, anaerobic motile bacteria suchas spirochetes, and anaerobic Gram negative rods including theblack-pigmented bacteroides are predominant. In other words, twodifferent microbial ecosystems are present on the same tooth surface.

A preferred antimicrobial agent for the treatment of periodontaldiseases is metronidazole. See U.S. Pat. No. 4,568,535 and Soskolne etal., J. Perio. Res., 18:330-336.

Periodontal disease is a condition caused by a pathogenic microbialecology established within the gingival sulcus which deepens to become aperiodontal pocket. This microbial ecology, located deep within theperiodontal pocket, differs greatly from that of the superficial oralenvironment by being more anaerobic, having a larger number of Gramnegative organisms, and having a greater proportion of motile species.

Several factors impede the diffusion of medicinal agents when applied tothe superficial periodontal tissues. Anatomically, the gum tissue isclosely adapted to the neck of the teeth, mechanically restricting thediffusional pathway. In addition, a fluid termed gingival crevice fluid,with the approximate composition of plasma, permeates the periodontalenvironment and is continually produced by the diseased periodontaltissues at a rate of 10 to 100 microliters per hour. This fluid,emanating from the diseased pocket lining, creates a net outward flowfurther impeding the introduction of medications from superficiallyapplied drug delivery devices. These interferences are sufficientlyeffective to insulate the pocket environment to the extent that salivadoes not penetrate, and topically applied medicinal agents have beenfound largely ineffectual in the treatment of established periodontitis.

Although mouth rinses may be effective in the reduction of superficialgingivitis resulting from poor home care procedures, the effectiveradius of action of these agents does not extend to the periodontalpocket. Introduction of antibacterial agents in solution form into theperiodontal pocket is similarly ineffective due to the rapid clearanceof such agents so that the duration of contact at the active site isminimal.

Conventional therapy for periodontal disease, as first enunciated byPierre Fauchard in 1746 in his book entitled "The Surgeon Dentist, aTreatise on Teeth," involves the mechanical removal of bacterial plaquesand accumulations from the periodontal pocket at periodic intervals.This may include periodontal surgery to achieve access and to recontourdamaged tissues. These procedures require a high degree of technicalexpertise from the practitioners of the art, are expensive, and oftenresult in pain, extensive bleeding, and general discomfort on the partof the patient so treated. Since these procedures provide, at best, onlytemporary reduction in bacterial populations, they must be repeated atregular intervals to be effective. As discussed by Lindhe and coworkersin "Healing Following Surgical/Non-Surgical Treatment of PeriodontalDisease" in the Journal of Clinical Periodontology, Vol. 9, pages115-128, the frequency of repetition needed for optimal results may beas high as once every two weeks.

Methods for administering drugs for periodontal therapy have heretoforelargely been concerned with superficial application. For example,long-acting capsules or tablets held in the mouth (see U.S. Pat. No.3,911,099); buccal implants for releasing drugs into the saliva (seeU.S. Pat. No. 4,020,558); topically applied gels (see U.S. Pat. No.3,679,360); topically applied drug-containing bandages (see U.S. Pat.No. 3,339,546); a drug-containing plastic hardenable mass (see U.S. Pat.No. 3,964,164); a medicated periodontal dressing (see U.S. Pat. No.3,219,527); a topical dressing composed of a finely divided particulatecarrier and suspended medicinal agents (see U.S. Pat. No. 3,698,392); abandage for covering moist mucosal surfaces (see U.S. Pat. No.3,339,546); a microencapsulated liquid droplet formation for topicalapplication to the gums of dogs and other animals (see U.S. Pat. No.4,329,333); and foam-film devices containing medication (see U.S. Pat.No. 3,844,286). In addition, several fibrous forms for superficialmedication have been described, including impregnated or drug-releasingforms of dental floss (see U.S. Pat. Nos. 3,417,179, 2,667,443,2,748,781, 3,942,539); solid absorbable fibers of polyglycolic acid withmedicants incorporated therein (see U.S. Pat. No. 3,991,766); andcellulose acetate hollow fibers (see U.S. Pat. No. 4,175,326). See alsoU.S. Pat. No. 4,892,736.

All of the foregoing references and the references cited in thesereferences are hereby incorporated herein by reference.

The ULTRAMULSION™ dispersions contained in the interdental deliverydevices of the present invention are distinct from other emulsions aswill become apparent from the following:

When a system consists of a single liquid phase it is described as asolution. A system containing two or more liquid phases is described asa multiphase solution or emulsion.

According to Becher, an emulsion is an unstable heterogeneous system inwhich the diameters of the dispersed droplets in general exceed 1000 Å.Becher P. in "Emulsions, Theory & Practice," (P. Becher, Ed.) page 2,Rheinhold, New York, 1965.

A more comprehensive definition of emulsion is advanced by Clayton: "Anemulsion is a system containing two liquid phases, one of which isdispersed as globules in the other. The liquid which is broken up intoglobules is termed the dispersed or discontinuous phase, while theliquid surrounding the globules is known as the continuous phase ordispersing medium" Clayton, W., "The Theory of Emulsions and TheirTechnical Treatment," 4th Ed. page 1, the Blakiston Co., Philadelphia,1943. It is well accepted that, mechanical work is required to affectsuch an emulsion, see Bancroft W. D., J. Phys. Phy. Chem., 17:501(1913).

According to Prince, an emulsion may be defined as a dispersion of two(or more) mutually insoluble liquids, one in the other. Because of thesurface tension forces at play between the two liquids, the dispersedphase consists of spherical droplets. Prince, L. M. in "MicroemulsionTheory & Practice," pg. 2, Academic Press Inc., New York, N.Y. (1977).See also Prince, L. M. in "Biological Horizons in Surface Science," pg.361, Academic Press Inc. (1973).

Emulsions, are generally not stable and upon standing or aftercentrifuging tend to separate into two or more liquid layers.

The three definitions of emulsions set forth above share one commonattribute, that is, mechanical work must be put into the emulsionsdescribed in order to disperse one liquid in the other in the form ofdroplets. This mechanical work can be in the form of agitation,homogenization, ultrasonication, and the like.

In contrast, dispersions of very small droplet sizes which are formedspontaneously without the input of any mechanical work are calledmicroemulsions. See Prince 1977, p. 3. Generally, two surfactants areused in forming microemulsions, i.e., a water soluble surfactant and aco-surfactant such as alcohol, where one phase of the microemulsion isgenerally water. Thus, dilution or adulteration of the dispersed phaseby the co-solvent generally accompanies microemulsion formation. Theratio of surfactant to dispersed phase in microemulsions is much higherthan that of emulsions. Microemulsions are further characterized asoptically clear or opalescent and when spun in a laboratory centrifugefor 5 minutes at 100 G's, the dispersion remains stable and does notseparate.

Thus, fine particle sizes, exceptional stability and rheologicalproperties that can be easily adjusted, distinguish microemulsions fromemulsions. Moreover, to date, no microemulsions have appeared in whichone of the mutually insoluble liquids is not water. See Prince, page 34,(1977).

It has been surprisingly found that certain ULTRAMULSION™ dispersions,i.e., those of the present invention, provide the interdental deliverydevices with improved antiplaque and antigingivitis, etc. performanceattributed to: (a) their enhanced substantivity, (b) the reservoireffect achieved by either dispersing certain ingredients in thediscontinuous silicone phase, or solubilizing various lipid solubleactive ingredients in the discontinuous silicone phase of theULTRAMULSION™ dispersion and (c) the generally small particle size ofthe dispersed silicone phase to effect suitable coatings in the oralcavity.

It is an object of the present invention to provide interdental deliverydevices containing ULTRAMULSION™ dispersion based antiplaque,antitartar, antigingivitis and periodontal treatment substances whichwhen released during use exhibit enhanced substantivity while containinga reservoir of various active ingredients for treating various oralhygiene conditions.

It is another object of the invention to provide a method formanufacturing the ULTRAMULSION™ dispersion containing interdentaldelivery devices of the invention.

It is yet another object of the invention to provide a method to treatvarious oral hygiene conditions with the interdental delivery devices ofthe present invention containing ULTRAMULSION™ dispersions.

It is another object of the present invention to provide ULTRAMULSION™dispersion containing interdental devices which release improved oralcare coatings.

It is also an object of this invention to provide an ULTRAMULSION™dispersion suitable for loading into various interdental deliverydevices without the need to resort to use of complex high energyprocesses.

It is a further object of the present invention to provide ULTRAMULSION™dispersion containing interdental delivery devices wherein various lipidsoluble and/or lipid dispersible actives are released from theULTRAMULSION™ dispersion coating released from the device during useinto the oral cavity over an extended period.

These and other objects will become readily apparent from the detaileddescription which follows.

Unless otherwise indicated, all percentages and ratios herein are byweight.

SUMMARY OF THE INVENTION

The ULTRAMULSION™ dispersions contained in the interdental deliverydevices of the present invention combine certain characteristics ofemulsions with certain features of microemulsions. That is, likeemulsions, they are two phase systems comprising a silicone dispersed ina continuous, surfactant phase, wherein the silicone is insoluble in thesurfactant. Unlike emulsions, but like microemulsions, these dispersionsare stable. Unlike microemulsions, but like emulsions, mechanical workis required to form ULTRAMULSION™ dispersions. Unlike microemulsions,but like emulsions, these ULTRAMULSION™ dispersions are not formedspontaneously. Like emulsions, the ULTRAMULSION™ dispersions do notcontain a cosolvent commonly found in microemulsions. Of course, theULTRAMULSION™ dispersions of the present invention can be dispersed invarious liquids such as water as stable dispersions.

While not wishing to be bound by theory, it is hypothesized that unlikeeither emulsions or microemulsions, the dispersed silicones of theULTRAMULSION™ dispersions contained in the interdental delivery devicesof the present invention are uniquely oriented with their polar moietiesin one general plane and their hydrophilic moieties in a planeapproximately opposite that of the polar moieties. This orientationpromotes stability as well as bonding between the polar or hydrophilicmoieties and various surfaces in the oral cavity thereby effectingoriented, monolayer coatings of the silicone onto these surfaces. Theseoriented dispersions of silicones have a surprising broad range ofutility in the devices of the present invention as detailed in thevarious examples below. This orienting is illustrated in FIGS. 1 & 2.

The emulsifying effects of uncoiling of the silicone molecule with theoxygen moieties generally oriented in one plane distinct from that ofthe organo moieties as illustrated in FIGS. 1 and 2, are furthersubstantiated by the following references: Eur. Poly. J., 26:654 (1990);J. Chem. Phys., 49:1398 (1965); J. Chem. Phys., 54:5011 (1971); J. Chem.Phys., 59:3825 (1973); Macromolecules, 7:229 (1974); Macromolecules,11:627 (1978) and "Rubber-Like Elasticity: A Molecular Primer," J. Mark,New York, Wiley-lnterscience, 1988.

Methods of preparing polyorganosiloxane emulsions with an averageparticle size of less than about 0.3 microns and polyorganosiloxanemicroemulsions with an average particle size of less than about 0.14micron are described in U.S. Pat. No. 4,620,878. Preparation ofoil-in-water microemulsions are described in U.S. Pat. No. 4,146,499.Specific surface active compositions used as emulsifiers withdiorganopolysiloxanes to form transparent microemulsions are describedin U.S. Pat. Nos. 4,0562,331 and 3,975,294, U.S. Pat. No. 3,433,780teaches the preparation of colloid silane suspensions. See also"Chemistry and Technology of Silicones," W. Noll, pp. 428 to 431 (1968);Journal of Society of Cosmetic Chemists, 25:609-619 (1974) and Journalof Colloid & Interface Science, 44:242-248 (1973).

Micellar dispersions, microemulsions, transparent emulsions aredescribed in detail in "Annals of the New York Academy of Science,"Shulman & Montagne (1961); U.S. Pat. No. 2,356,205, "The Theory ofEmulsions & Their Technical Treatment," 5th Edition, 1954, U.S. Pat.Nos. 3,497,006; 3,506,070, 3,254,714 and 3,307,628.

The ULTRAMULSION™ dispersions of silicones in surfactants contained inthe interdental delivery devices of the present invention as describedherein are neither taught nor suggested by the foregoing references.

The routine treatment of interproximal and subgingival areas as well asperiodontal pockets with an interdental delivery device containingULTRAMULSION™ dispersions which are released onto the surface beingtreated is unique, not only because of the unexpected substantivity ofthe released ULTRAMULSION™ dispersion to the oral surface but alsobecause the "reservoir" effect of the resultant silicone based coatingwhich affects on going relief, well after treatment with the interdentaldevice is discontinued.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the "coiled" molecular configuration proposed forpolydimethylsiloxanes;

FIG. 2 illustrates the proposed molecular configuration of orientedpolydimethylsiloxanes after ULTRAMULSION™ dispersion processing;

FIG. 3 illustrates schematically an ULTRAMULSION™ dispersion process ofthe invention;

FIGS. 4 and 5 illustrate that the ULTRAMULSION™ dispersions of theinvention produced via various high shear dispersing means havingparticle size distribution of 80+% under 10 microns; and

FIGS. 6 and 7 are a graph and a chart respectively showing the effect ofincreased silicone viscosity on plaque buildup in a certain oral careproduct.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, FIG. 1 illustrates the accepted "coiled"configuration advanced for polydimethylsiloxanes, wherein the methylmoieties are oriented outward while the oxygen moieties are orientedinward towards the axis of the coil or helix. This configuration doesnot readily promote "bonding" between the oxygen moieties and compatiblesurfaces such as those in the oral cavity.

FIG. 2 illustrates the "uncoiled oriented" configuration proposed forpolydimethylsiloxanes that have been dispersed in the stable,ULTRAMULSION™ dispersion of the present invention, wherein the oxygenmoieties are generally oriented in one plane distinct from that of themethyl moieties. This proposed uncoiled oriented configuration appearsto support the unique and unexpected stability "bonding and enhancedsubstantivity" properties of the ULTRAMULSION™ dispersion of the presentinvention, as evidenced by the various treatments that can be affectedwith the ULTRAMULSION™ dispersion containing devices of the presentinvention. See examples below.

FIG. 3 illustrates the ULTRAMULSION™ dispersion interdental deliverydevice loading process of the present invention wherein a nonionicsurfactant and a polydimethyl-siloxane 1, substantially free from waterand co-solvent, are mixed in vessel 2, provided with mixing means 3,heat source 4, and inert head space 5. The heated and mixed surfactantand poly-dimethylsiloxane 6, is then subjected to high shear dispersionat an elevated temperature in dispersing means 7, to produce theULTRAMULSION™ dispersion 8, of the invention, which is suitable forintroduction into a vacuum chamber 9, to which interdental devices 10have been added. Applying vacuum to chamber 9 removes air from devices10 and allows ULTRAMULSION™ dispersion 11 to fill the voids from whichair has been removed upon release of the vacuum.

FIG. 4 is a chart describing the particle size distribution of anULTRAMULSION™ dispersion of the invention containing 95-5% by weightnonionic surfactant and 5-50% by weight polydimethylsiloxane (2.5million cs) produced in a continuous process with an IKA Work dispersingmeans, (high shear dispersing) with an inlet temperature of 140° C. andan outlet temperature of 210° C.

FIG. 5 is a chart describing the particle size distribution of anULTRAMULSION™ dispersion of the invention containing 95-50% by weightnonionic surfactant and 5-50% by weight polydimethylsiloxane (2.5million cs) produced;in a batch process with a Ross M/E 100 LCdispersing means fitted with a 20 mesh screen, operated at a temperaturefrom 120° to 160° C.

FIGS. 6 and 7 disclose the influence of increasing viscosity of thesilicone in the ULTRAMULSION™ dispersion on the anti-plaque effect ofthis ULTRAMULSION™ dispersion when introduced into the oral cavityseveral times throughout the day as a mint. This reduction in plaquebuildup is a substantial advance in establishing the efficacy and valueof away-from-home oral care products such as mints. Similar anti-plaqueresults are produced upon treating teeth and gums with interdentaldelivery devices of the present invention containing ULTRAMULSION™dispersions.

These same ULTRAMULSION™ dispersions can further contain various lipidsoluble active ingredients in the dispersed silicone phase and therebyimpart extended anti-plaque, anti-tartar, anti-gingivitis and/oranti-periodontia effects to various interdental delivery devicescontaining these ULTRAMULSION™ dispersions. This "reservoir" effect ofsilicones containing active ingredients was documented with triclosancontaining toothpaste by Rolla et al., in clinical studies reported inScand. J. Dent. Res., 101:130-138.

The ULTRAMULSION™ dispersion can contain various agents found to beeffective in treating periodontal pockets such as metronidazole,antibiotics such as tetracycline and penicillin and mixtures of suchpathogen specific substances as described by Genco in J. Periodontology,52:545-558 (1981) and U.S. Pat. No. 4,892,736 and "Medical Applicationsof Controlled Release," CRC Press, Boca Raton 1984.

Heretofore these periodontal pockets were fitted with "slow release"films etc. containing antimicrobials and/or antibiotics etc. such asdescribed by Goodson in U.S. Pat. No. 4,892,736 and Loesche in U.S. Pat.No. 4,568,535 and the pocket then "packed" with a periodontal dressing.It is suggested these perio-pockets can be treated interdental deliverydevices of the present invention containing various ULTRAMULSION™dispersions wherein the silicone dispersed phase contains the activeingredient and releases the active ingredient from the siliconereservoir released into perio pocket. This "pocket" treatment withdevices of the present invention would be repeated several timesthroughout the day.

For purposes of the present invention, the term silicone means a clear,colorless substance containing polydialkylsiloxane polymers with averagekinematic viscosities ranging from about 100,000 centistokes (cs) toabout 50 million cs, preferably from about 1 million cs to about 25million cs, more preferably from about 1.5 million cs to about 10million cs, and most preferably from about 2 million to about 5 millioncs. This definition intentionally includes the so-called "gum" siliconeshaving viscosities of 30 to 50 million cs. Certain high viscositypolydimethylsiloxanes having viscosities from about 2.5 million cs toabout 4 million cs are particularly preferred for the hair care productsof the present invention. Other polydimethylsiloxanes suitable for thepresent invention, include "substituted" water insoluble silicones andmixtures of polydiorganosiloxanes and substituted water insolublesilicones. Specifically, water soluble silicones are excluded from theULTRAMULSION™ dispersions of file present invention.

The viscosity of some silicones can be measured by means of a glasscapillary viscometer as set forth in Dow Corning Corporate Test MethodCTM0004, Jul. 20, 1970.

The Silicone fluid may be either a high viscosity polyalkyl siloxane asdescribed in detail below. Mixtures of various silicones may also beused and are preferred in certain embodiments of the invention.

The polyether siloxane copolymer that may be used is, for example, apolypropylene oxide modified dimethylpolysiloxane although ethyleneoxide or mixtures of ethylene oxide and propylene oxide may also beused.

References disclosing suitable silicone fluids include U.S. Pat. No.2,826,551 to Green; U.S. Pat. No. 3,964,500 to Drakoff; U.S. Pat. No.4,364,837 to Padner and British Pat. No. 849,433 to Woolston. All ofthese patents are hereby incorporated herein by reference. Alsoincorporated herein by reference is Silicon Compounds distributed byPetrarch Systems, Inc., 1984. This reference provides a very goodlisting of suitable silicone materials.

Silicone materials found especially useful in the present devices toprovide good oral hygiene results are silicone gums. Silicone gumsdescribed by Petrarch and others including U.S. Pat. No. 4,152,416, May1, 1979 to Spitzer et al., and Noll, Walter; Chemistry and Technology ofSilicones, New York, Academic Press 1968. Also describing silicone gumsare various General Electric Silicone Rubber Product Data Sheets. All ofthese described references are incorporated herein by reference."Silicone gum" materials denote high molecular weightpolydiorganosiloxanes having a viscosity up to about 50 million cs.Specific examples include polydimethylsiloxane, polydimethylsiloxane,methylvinylsiloxane, copolymer, poly(dimethylsiloxane, diphenyl,methylvinylsiloxane copolymer and mixtures thereof.

As noted above high viscosity polydimethylsiloxanes i.e., those above100,000 cs are preferred. Particularly preferred arepolydimethylsiloxanes from between about 2.5 million cs and about 50million cs. The safety of polydimethylsiloxanes for use in these variousproducts is well documented. See Rowe et al., Journal of IndustrialHygiene, 30:332-352 (1948). See also Calandra et al., "ACS PolymerPreprints," 17:1-4 (1976) and Kennedy et al., J. Toxicol. &Environmental Health, 1:909-920 (1976).

As noted above, preferred polydimethylsiloxanes useful in theinterdental delivery devices of the present invention are described aspolymethylsiloxanes with the chemical composition:

    (CH.sub.3).sub.3 SiO[SiO(CH.sub.3).sub.3 ].sub.n Si(CH.sub.3).sub.3

wherein n is a whole number. These polydimethylsiloxanes haveviscosities up to 50 million cs. and are generally described as havinghigh molecular weights.

The particle size of the silicone in the ULTRAMULSION™ dispersion of thepresent invention can range from between about 0.1 and about 10 microns.In a preferred embodiment of the present invention the particle size ofpolydimethylsiloxanes in the ULTRAMULSION™ dispersion ranges frombetween about 1 and about 5 microns. The particle size distribution ofthe polydimethylsiloxanes in the ULTRAMULSION™ dispersion of the presentinvention generally range from between about 80 and about 95% of theparticles under 10 microns. See FIGS. 4 and 5. In a preferred embodimentof the present invention, from between about 80 and about 95% of theparticles are under 5 microns. See also Table 2.

An essential component of the ULTRAMULSION™ dispersion is a surfactant.The surfactant, may be selected from any of a wide variety of syntheticanionic, amphoteric, zwitterionic and nonionic surfactants, that aresafe for use in the oral cavity.

The surfactants suitable for the purposes of the present invention mustfunction as the continuous phase and contain the disposal discontinuoussilicone phase. Generally, these surfactants are liquid or meltablesubstances and include mixtures of surfactants as detailed in theexamples and tables below.

Synthetic anionic surfactants can be exemplified by the alkali metalsalts of organic sulfuric reaction products having in their molecularstructure an alkyl radical containing from 8-22 carbon atoms and asulfonic acid or sulfuric acid ester radical (included in the term alkylis the alkyl portion of higher acyl radicals). Preferred are the sodium,ammonium, potassium or triethanolamine alkyl sulfates, especially thoseobtained by sulfating the higher alcohols (C₈ -C₁₈ carbon atoms), sodiumcoconut oil fatty acid monoglyceride sulfates and sulfonates; sodium orpotassium salts of sulfuric acid esters of the reaction product of 1mole of a higher fatty alcohol (e.g., tallow or coconut oil alcohols)and 1 to 12 moles of ethylene oxide ether sulfate with 1 to 10 units ofethylene oxide per molecule and in which the alkyl radicals contain from8 to 12 carbon atoms, sodium alkyl glycerol ether sulfonates; thereaction product of fatty acids having from 10 to 22 carbon atomsesterified with isethionic acid and neutralized with sodium hydroxide;water soluble salts of condensation products of fatty acids withsarcosine; and other known in the art.

Zwitterionic surfactants can be exemplified by those which can bebroadly described as derivatives of aliphatic quaternary ammonium,phosphonium, and sulfonium compounds, in which the aliphatic radicalscan be straight chain or branched, and wherein one of the aliphaticsubstituents contains from about 8 to 18 carbon atoms and one containsan anionic water-solubilizing group, e.g., carboxyl, sulfonate, sulfate,phosphate, or phosphonate. A general formula for these compounds is:##STR1## wherein R² contains an alkyl, alkenyl, or hydroxyl alkylradical of from about 8 to 18 carbon atoms, from 0 to about 10 ethyleneoxide moieties and from 0 to 1 glycerol moiety; Y is selected from thegroup consisting of nitrogen, phosphorous, and sulfur atoms; R³ is analkyl or monohydroxyalkyl group containing 1 to about 3 carbon atoms; Xis 1 when Y is a sulfur atom and 2 when Y is a nitrogen or phosphorousatom; R⁴ is an alkylene or hydroxyalkylene of from 1 to about 4 carbonatoms and Z is a radical selected from the group consisting ofcarboxylate, sulfonate, sulfate, phosphonate, and phosphate groups.

Examples include:

4-[N,N-di(2-hydroxyethyl)-N-octadecylammonio]-butane-1-carboxylate;

5-(S-3-hydroxypropyl-S-hexadecylsulfonio]-3-hydroxypentane- 1-sulfate;

3-[P,P-diethyl-P-3,6,9-trioxatetradexocylphosphonio]-2-hydroxypropane-1-phosphate;

3-[N,N-dipropyl-N-3-dodecoxy-2-hydroxypropylammonio]-propane-1-phosphate;

3-[N,N-dimethyl-N-hexadecylammonio-propane-1-sulfonate;

4-[N,N-di(2-hydroxyethyl)-N-(2-hydroxydodecyl)ammonio]-butane-1-carboxylate;

3-[S-ethyl-S-(3-dodecoxy-2-hydroxypropyl)sulfonio]-propane-1-phosphate;

3-[P,P-dimethyl-P-dodecylphosphonio]-propane-1-phosphonate; and

5-(N,N-di(3-hydroxypropyl)-N-hexadecylammonio]-2-hydroxypentane-1-sulfate.

Other zwitterionics such as betaines are also useful in the presentinvention. Examples of betaines useful herein include the higher alkylbetaines such as cocodimethyl carboxymethyl betaine, lauryl dimethylcarboxymethyl betaine, lauryl dimethyl alpha-carboxyethylene betaine,cetyl dimethyl carboxymethyl betaine, lauryl bis-(2-hydroxyethyl)carboxymethyl betaine, stearyl bis-(20-hydroxypropyl)carboxymethyl betaine,oleyl dimethyl gamma-carboxypropyl betaine, laurylbis-(2-hydroxypropyl)alpha-carboxyethyl betaine, etc. The sulfobetainesmay be represented by cocodimethyl sulfopropyl betaine, stearyl dimethylsulfopropyl betaine, lauryl dimethyl sulfoethyl betaine, laurylbis-(2-hydroxy-ethyl)sulfopropyl betaine and the like; amido betainesand amidosulfo betaines, wherein the RCONH(CH₂)₃ radical is attached tothe nitrogen atom of the betaine are also useful in this invention. Theamido betaines are preferred for use in some of the compositions of thisinvention. A particularly preferred composition utilizes an amidobetaine, a quaternary compound, a silicone, a suspending agent and has apH of from about 2 to about 4.

Examples of amphoteric surfactants which can be used in theULTRAMULSION™ dispersion of the present invention are those which can bebroadly described as derivatives of aliphatic secondary and tertiaryamine in which the aliphatic radical can be straight chain or branchedand wherein one of the aliphatic substituents contains from about 8 toabout 18 carbon atoms and one contains an anionic water solubilizinggroup, e.g., carboxy, sulfonate, sulfate, phosphate, or phosphonate.Examples of compounds falling within this definition are sodium3-dodecylamino-propionate, sodium 3-dodecylamino-propane sulfonate,N-alkyltaurines such as the one prepared by reacting dodecylamine withsodium isethionate according to the teaching of U.S. Pat. No. 2,658,072,N-higher alkyl aspartic acids such as those produced according to theteaching of U.S. Pat. No. 2,438,091, and the products sold under thetrade name "Miranol" and described in U.S. Pat. No. 2,528,378.

Nonionic Surfactants, which are preferably used in combination with ananionic, amphoteric or zwitterionic surfactant, can be broadly definedas compounds produced by the condensation of alkylene oxide groups(hydrophilic in nature) with an organic hydrophobic compound, which maybe aliphatic or alkyl aromatic in nature. Examples of preferred classesof nonionic surfactants are:

1. The polyethylene oxide condensates of alkyl phenols, e.g., thecondensation products of alkyl phenols having an alkyl group containingfrom about 6 to 12 carbon atoms in either a straight chain or branchedchain configuration, with ethylene oxide, the said ethylene oxide beingpresent in amounts equal to 10 to 60 moles of ethylene oxide per mole ofalkyl phenol. The alkyl substituent in such compounds may be derivedfrom polymerized propylene, disobutylene, octane, or nonane, forexample.

2. Those derived from the condensation of ethylene oxide with theproduct resulting from the reaction of propylene oxide andethylenediamine products which may be varied in composition dependingupon the balance between the hydrophobic and hydrophilic elements whichis desired. For example, compounds containing from about 40% to about80% polyoxyethylene by weight and having a molecular weight of fromabout 5,000 to about 15,000 resulting from the reaction of ethyleneoxide groups with a hydrophobic base constituted of the reaction productof ethylene diamine and excess propylene oxide, said base having amolecular weight of the order of 2,500 to 3,000 are satisfactory.

3. The condensation product of aliphatic alcohols having from 8 to 18carbon atoms, in either straight chain or branched chain configuration,with ethylene oxide, e.g., a coconut alcohol ethylene oxide condensatehaving from 10 to 30 moles of ethylene oxide per mole of coconutalcohol, the coconut alcohol fraction having from 10 to 14 carbon atoms.

4. Long chain tertiary amine oxides corresponding to the followinggeneral formula: ##STR2## wherein R₁ contains an alkyl, alkenyl ormonohydroxy alkyl radical of from about 8 to about 18 carbon atoms from0 to about 10 ethylene oxide moieties, and from 0 to 1 glycerol moiety,and R₂ and R₂ contains from 1 to about 3 carbon atoms and from 0 toabout 1 hydroxy group, e.g., methyl, ethyl, propyl, hydroxy ethyl, orhydroxypropyl radicals. The arrow in the formula is a conventionalrepresentation of a semipolar bond. Example of amine oxides suitable foruse in this invention include dimethyl-dodecylamine oxide,oleyldi(2-hydroxy-ethyl)amine oxide, dimethyloctylamine oxide,dimethyl-decylamine oxide, dimethyltetradecylamine oxide.3,6,9-trioxaheptadecyldiethylamine oxide,di)2-hydroxyethyl)-tetracylamine oxide, 2-dodecoxyethyldimethylamineoxide, 3-dodecoxy-2-hydroxypropyldi-(3-hydroxy-propyl)amine oxide,dimethylhexadecylamine oxide.

5. Long chain tertiary phosphine oxides corresponding to the followinggeneral formula: ##STR3## wherein R contains an alkyl, alkenyl ormonohydroxyalkyl radical ranging from 8 to 18 carbon atoms in chainlength from 0 to about 10 ethylene oxide moieties and from 0 to 1glycerol moiety and R' and R" are each alkyl or monohydroxyalkyl groupscontaining from 1 to 3 carbon atoms. The arrow in the formula is aconventional representation of a semipolar bond. Examples of suitablephosphine oxides are: dodecyldimethylphosphine oxide,tetradecyl-dimethylphosphine oxide, tetradecylmethylethylphosphineoxide. 3,6,9-trioxaoctadecyldimethylphosphine oxide,cetyldimethylphosphine oxide,3-dodecoxy-2-hydroxypropyl-di(2-hydroxyl)phosphine oxide,stearyldimethylphosphine oxide, cetylethylpropylphosphine oxide,cetyldiethylphosphine oxide, dodecyl-diethylphosphine oxide,tetradecyldiethylphosphine oxide, dodecyldipropylphosphine oxide,dodecyldi(2-hydroxyethyl)phosphine oxide,tetradecylmethyl-2-hydroxydodecyldimethylphosphine oxide.

6. Long chain dialkyl sulfoxides containing one short chain alkyl orhydroxy alkyl radical of 1 to about 3 carbon atoms (usually methyl) andone long hydrophosphic chain which contain alkyl, alkenyl, hydroxyalkyl, or keto alkyl radicals containing from about 8 to about 20 carbonatoms, from 0 to about 10 ethylene oxide moieties and from 0 to 1glycerol moiety. Examples include: octadecyl menthyl sulfoxide,2-ketotridecyl methyl sulfoxide, 3,6,9,-trioxooctadecyl 2-hydroxyethylsulfoxide, dodecyl menthyl sulfoxide, oleyl 3-hydroxypropyl sulfoxide,tetradecyl menthyl sulfoxide, 3-methoxytridecyl methyl sulfoxide,3-hydroxytridecyl methyl sulfoxide, 3-hydroxy-4-dodecoxybutyl methylsulfoxide.

Many additional nonsoap surfactants are described in McCUTCHEON'S,DETERGENTS AND EMULSIFIERS, 1979 ANNUAL, published by Allured PublishingCorporation which is incorporated herein by reference.

Particularly preferred nonionic surfactants are nonionic poloxamersurfactants of block copolymers of ethylene oxide and propylene oxideranging from flowable liquids of varying viscosities, to paste, prillsand cast solids with molecular weights from 1,100 to 150,000. Suitablenonionic surfactants are manufactured and marketed by BASF Corporationunder the trademarks Pluronic. Particularly preferred nonionicsurfactants are Pluronic F-68, F-88, F-108 and Pluronic F-127. These aredescribed in a BASF brochure entitled "Pluronic and Tetronic BlockCopolymer Surfactant." These nonionic surfactants suitable for thepresent invention can be described by the following structure: ##STR4##where x, y and x' are whole numbers. Surprisingly, the nonionicsurfactants of choice for the ULTRAMULSION™ dispersion of the presentinvention are reported in the referenced brochure to have marginaldetergency, emulsification and wetting properties. See Tables 1 and 2.

As noted above, the preferred nonionic poloxamer surfactants useful inthe coating compositions of the present invention are described aspolyoxyethylene-polyoxypropylene block copolymers such as Pluronic F-68,F-88, F-108 and F-127 (BASF) which have molecular weights of at leastabout 1000 such as described in U.S. Pat. Nos. 4,343,785, 4,465,663,4,511,563 and 4,476,107, the disclosures of which are herebyincorporated herein by reference.

Emulsions of various coating substances including polydimethylsiloxanesin various surfactants including nonionic surfactants are disclosed andclaimed in U.S. Pat. Nos. 4,911,927, 4,942,034; 4,950,479; 5,009,881;5,032,387; 5,057,306; 5,057,307; 5,057;308, 5,057,309; 5,057,310,5,098,711, 5,165,913 and 5,284,648. There is no teaching in thesereferences that these highly viscosity silicone emulsions are stable northat the "coating" substances are oriented as they are in theULTRAMULSION™ dispersions of the present invention.

The ratio of surfactant to silicone in the ULTRAMULSION™ dispersioncoating compositions for use in the devices of the present invention canrange from between about 400:1 and about 1:2. In a preferred embodimentof the invention the ratio of surfactant to silicone is from betweenabout 25:1 and 1:2. See Tables 1 and 2.

For the purposes of the present invention:

a. stable is defined as, dispersing the ULTRAMULSION™ dispersion inwater, subjected said dispersion to centrifuging in a 100 G environmentfor 5 minutes, with less than about 10% by weight of the ULTRAMULSION™dispersion separating from the continuous water phase and/or asubstantial portion of the dispersed phase resists separation. Thislatter definition is particularly applicable to higher viscositysilicones. See Table 2.

b. water-free means, that the ULTRAMULSION™ dispersion of silicone andsurfactant is substantially free from water.

c. solvent free means, that the ULTRAMULSION" dispersion of silicone andsurfactant is substantially free from co-solvents such as ethanol,isopropanol, and the like.

d. oriented means, that the polar moieties of the "uncoiled"polydimethylsiloxane in the ULTRAMULSION™ dispersion are generallyaligned in one plane with the hydrophilic oil seeking moieties alignedin a second plane such as illustrated in FIG. 2.

e. monolayer means, that the monomolecular film of the ULTRAMULSION™dispersion contained in the devices of the invention when dispersed inwater is attracted to mucosa and hydroxyapatite by secondary bondingforces to form a substantive coating thereon.

The ULTRAMULSION™ dispersions to be loaded into the devices of thepresent invention are prepared as follows:

Generally, if not a liquid, the surfactant is heated to a temperature atwhich it becomes a liquid. The silicone is dispersed in the heatedsurfactant with various high shear dispersing means.

Specifically the heated surfactant is mechanically stirred along withthe silicone to form a pre-emulsion mixture in which the silicone isuniformly dispersed in the surfactant in droplets of a larger size thendesired for the ULTRAMULSION™ dispersion but small enough to optimizethe subsequent high shear dispersions. This mixture is subjected tohigh-shear dispersions with a means such as the IKA-WORKS DISPAX-Reactorwith at least one superfine generator, alternatively, a Ross Model M.E., 100 LC fitted with a 20 mesh screen or a ultrasonicator such asMEDSONIC XL2010 fitted with 800-C Flow Cell & 800-21CT 3/4 inch flangedhorn can be used.

Various ULTRAMULSION™ dispersions which are prepared and analyzed aredescribed in detail in the examples below.

                  TABLE 1                                                         ______________________________________                                        ULTRAMULSION ™ DISPERSION COMPOSITION                                      % W/W                                                                                  Example No.                                                          Component  1     2     3   4   5   6   7   8   9   10  11                     ______________________________________                                        Dimethicone                                                                   viscosity-centistokes                                                           100,000  10    --    --  --  --  --  --  --  --  33  --                       600,000  --    10    --  --  --  --  33  --  --  --  --                      2,500,000 --    --    10  --  --  --  --  33  --  --  10                      4,000,000 --    --    --  10  --  --  --  --  33  --  --                     30,000,000 --    --    --  --  10  --  --  --  --  --  --                     50,000,000 --    --    --  --  --  10  --  --  --  --  --                     Poloxamer - 188                                                                          --    --    --  --  --  --  --  --  --  67  --                     Poloxamer - 238                                                                          --    --    --  --  --  --  --  --  --  --  90                     Poloxamer - 338                                                                          90    90    90  90  90  90  --  --  --  --  --                     Poloxamer - 407                                                                          --    --    --  --  --  --  67  67  67  --  --                     ______________________________________                                    

Specific poloxamer/polydimethylsiloxane ULTRAMULSION™ dispersionssuitable for use with interdental delivery devices were prepared andanalyzed as described in Table 2 below:

                                      TABLE 2                                     __________________________________________________________________________    ULTRAMULSION ™ DISPERSION - COMPOSITION                                    % W/W                                                                                  Example No.                                                          Component                                                                              12 13 14 15 16 17 18 19 20 21                                        __________________________________________________________________________    Dimethicone                                                                   viscosity-centistokes                                                           600,000                                                                              -- 11.6                                                                             -- -- -- 10.0                                                                             -- -- -- --                                         2,500,000                                                                             10.0                                                                             -- -- 11.9                                                                             11.9                                                                             -- -- -- -- 14.0                                       4,000,000                                                                             -- 11.6                                                                             -- -- -- -- -- -- -- --                                        30,000,000                                                                             -- -- -- -- -- 11.6                                                                             -- -- -- --                                        50,000,000                                                                             -- -- -- -- -- -- 11.6                                                                             10.0                                                                             -- --                                        __________________________________________________________________________

                  TABLE 3                                                         ______________________________________                                        ULTRAMULSION ™ DISPERSION - COMPOSITION                                    % W/W                                                                                      Example No.                                                      Lipid Soluble/Dispersable                                                                    12     13     14   15   16   17                                ______________________________________                                        Component Mixture Of:                                                         Thymol - 24%   10.0   --     --   --   --   --                                Menthol - 16%  10.0   --     --   --   --   --                                Eucalyptol - 36%                                                                             10.0   --     --   --   --   --                                Methyl Salicylate - 24%                                                                      10.0   --     --   --   --   --                                Stannous Fluoride                                                                            --     --     --   --   --    1.75                             Triclosan      --      1.16  --   --   --   --                                Chorhexdidine  --     --      2.0 --   --   --                                Metronidazole  --     --     --    1.3 --   --                                Benzocaine     --     --     --   --    1.0 --                                Poloxamer 338  90.0   98.84  98.0 98.7 99.0 98.05                             Dimethethicone - 2,500,000                                                    CENTISTOKES                                                                   80:20                                                                         POLOXAMER:DIMETHI-                                                            CONE                                                                          ______________________________________                                    

As noted above, the discontinuous silicone phase of the ULTRAMULSION™dispersion can also contain a wide range of lipid soluble and/or lipiddispersible oral care active ingredients ranging from antimicrobials todesensitizing/substances, to healants such as aloe to vitamins such asvitamin E, to flavorants, etc. These various ingredients in the siliconephase of the ULTRAMULSION™ dispersion perform in various interdentaldelivery devices once they are released from the device as though theyare contained in a "reservoir" as they continue to be available at theULTRAMULSION™ dispersion oral surface interface, as long as theULTRAMULSION™ dispersion coating remains substantive to mouth surfaces.Similar effects attributed to this reservoir effect are described byRolla et al., supra.

The interdental delivery device of the present invention containing theULTRAMULSION™ dispersions will contain a variety of essential componentsranging from surfactants for cleaning, to whiteners, to flavorants etc.These are detailed in various Examples described below.

Water is an essential component of most oral care products of thepresent invention which contain one or more of the various ULTRAMULSION™dispersions described above. The water in these products is generallypresent at a level of from about 5% to about 95%, preferably frombetween about 60% and about 90%.

In addition these oral care products can contain a variety ofnonessential optional components suitable for rendering suchcompositions more acceptable. See Tables 3 to 6 below.

Such conventional optional ingredients are well known to those skilledin the art, e.g., preservatives such as benzyl alcohol, methyl paraben,propyl paraben and imidiazolidinyl urea; cationic surfactants such ascetyl trimethylammonium chloride, lauryl trimethyl ammonium chloride,tricetyl methyl ammonium chloride, stearyldimethyl benzyl ammoniumchloride, and di(partially hydrogenated tallow)dimethylammoniumchloride; thickeners and viscosity modifiers such as diethanolamide of along chain fatty acid (e.g., PEG 3 lauramide), block polymers ofethylene oxide and propylene oxide such as Pluronic F88 offered by BASFWyandotte, sodium chloride, sodium sulfate, polyvinyl alcohol, and ethylalcohol; pH adjusting agents such as citric acid, succinic acid,phosphoric acid, sodium hydroxide, sodium carbonate, etc., perfumes;dyes; and, sequestering agents such as disodium ethylenediaminetetraacetate. Such agents generally are used individually at a level offrom about 0.01% to about 10%, preferably from about 0.5% to about 5.0%by weight of the composition.

The ULTRAMULSION™ dispersions of the invention are particularly usefulin interdental devices whose use is under supervision of a professional.The inclusion of stannous fluoride in the discontinuous phase of theemulsion is particularly attractive as a means of treating interproximalcaries. See Segueto et al., Journal of Dental Research, Vol. 10, No. 1,pp. 90-96, 1961 and Peterson et al., Northwest Dentistry, 276-278,Sep./Oct. 1963.

The pH of the ULTRAMULSION™ dispersions is preferably from about 6 to 8.

METHOD OF MANUFACTURE

The various interdental delivery devices of the present invention can bemade by mixing the ULTRAMULSION™ dispersion materials together andheating if necessary and following accepted manufacturing practices asdescribed in detail below.

INDUSTRIAL APPLICABILITY

The products of the present invention have utility in a wide range oforal care products as illustrated below.

The examples set forth in Tables IV through VIII further describe anddemonstrate preferred embodiments within the scope of the presentinvention. The examples are given solely for the purpose of illustrationand are not to be construed as limitations of the present invention asmany variations thereof are possible without departing from its spiritand scope.

                  TABLE IV                                                        ______________________________________                                        INTERDENTAL DEVICE FORMULATIONS                                               % W/W                                                                                 Example #                                                             Component 18      19      20     21     22                                    ______________________________________                                        Ultramulsion                                                                            (1) 12  (3) 12  (12) 15.0                                                                            (14) 11.0                                                                            (13) 9.0                              from Example II                                                               Sorbitol -                                                                              7.5     7.5     8.0    9.0    7.0                                   70% Aq.                                                                       Sodium Saccharin                                                                        0.4     0.4     0.4    0.4    0.4                                   Flavor    5.0     5.0     5.4    5.1    4.8                                   D.I. Water                                                                              75.1    75.1    71.2   74.5   78.8                                  ______________________________________                                    

Procedure for Impregnating Interdental Stimulators

1. Material to be impregnated (e.g., wooden sticks) with theULTRAMULSION™ dispersion (or formulation) is placed in suitablecontainer capable of holding a vacuum, such as a desiccator, stainlesssteel covered reactor or similar device.

2. The liquid formulation is poured on top of the material and coveredcompletely by the liquid. A perforated disk with ballast is placed onthe material to keep from floating.

3. The container is then sealed, and vacuum applied for varying periodsof time ranging from 1 min. to several hours with the preferred timebeing between 5-10 min.

4. Vacuum is maintained such that the liquid does not boil, but enoughvacuum to remove entrapped air from the device.

Example of laboratory preparation using wooden interdental Stimulators(IDS)

Collectively, 87.0 grams of wooden interdental stimulators (IDS) equalsabout 260 individual stimulators. This IDS batch was impregnated withthe ULTRAMULSION™ dispersion formulation from Example 22 under vacuum,at 30 mm of mercury for a period of 10 minutes. The resultingimpregnated IDS batch was removed from the remaining solution and driedat 40° C. in convection oven for 1.5 hour. The IDS were dry and thefinal batch weight was 152.7 grams. This is a 56.9% increase in weightindicating the amount of dry formulation impregnated into the IDS.

Similar results were obtained with the ULTRAMULSION™ dispersionformulations of Examples 18-21.

The present invention has been described in detail, including thepreferred embodiments thereof. However, it will be appreciated thatthose skilled in the art, upon consideration of the present disclosure,may make modifications and/or improvements on this invention and stillbe within the scope and spirit of this invention as set forth in thefollowing claims.

What is claimed is:
 1. A non-floss type interdental delivery devicecontaining an ULTRAMULSION which is a high shear dispersion of asilicone in a surfactant formed by heating a mixture of surfactant andsilicone, followed by high shear mixing, said ULTRAMULSION dispersionbeing released into the oral cavity when the device is used to clean,massage and/or treat surfaces in the mouth, wherein:a. the silicone isinsoluble in said surfactant, has a viscosity greater than about 100,000cs, and a particle size up to about 10 microns, b. the surfactant tosilicone ratio in the high shear dispersion is from between about 400:1and about 1:1; and the surfactant has an orienting effect on thesilicone, c. the silicone is oriented, exhibits enhanced substantivityto surfaces in the oral cavity and functions as a reservoir for one ormore lipid soluble and lipid dispersible oral care active ingredients.2. An interdental device according to claim 1, wherein said ULTRAMULSIONdispersion comprises a nonionic poloxamer surfactant andpolydimethylsiloxane wherein:a. said polydimethylsiloxane has thechemical composition (CH₃)₃ SiO[SiO(CH₃)₂ ]_(n) Si(CH₃)₃, wherein n is awhole number; b. said surfactant has the chemical composition ##STR5##wherein x, y, and x' are whole numbers; c. the viscosity of thepolydimethylsiloxane ranges from between about 2.5 million and about 50million cs; d. the particle size of most of the polydimethylsiloxane inthe ULTRAMULSION dispersion is from between about 0.1 and about 10microns; e. from between about 80% and 95% of said polydimethylsiloxaneparticles in the ULTRAMULSION dispersion are from between about 0.1 andabout 10 microns; f. the nonionic surfactant is apolyoxyethylene-polyoxypropylene block copolymer having a molecularweight from between about 1,100 and about 150,000; g. the ratio ofsurfactant to polydimethylsiloxane is from between about 400:1 and about1:2; and h. the ULTRAMULSION dispersion is loaded into the device atfrom between about 1 and about 25% by weight of said device.
 3. Aninterdental device according to claim 2, wherein the ratio of saidsurfactant to said silicone 9:1 and 90% of the silicone particles arefrom between about 1 and 3 microns.
 4. An interdental device accordingto claim 2, wherein the ratio of said surfactant to said silicone is 2:1and 100% of the silicone dispersion is less that 10 microns.
 5. Aninterdental device according to claim 2, wherein the ratio of saidsurfactant to said silicone is 1:1 and the silicone particles in saidULTRAMULSION dispersion are less than 10 microns.
 6. A non-floss typeinterdental delivery device according to claim 2, wherein the ratio ofsurfactant to polydimethylsiloxane is 1:1 and at least 80% of thepolydimethylsiloxane dispersed particles are between 1 and 9 microns. 7.A non-floss type interdental device according to claim 2, wherein theratio of surfactant to polydimethylsiloxane is 4:1 and about 90% of thepolydimethylsiloxane dispersed particles are between 1 and 9 microns. 8.A non-floss type interdental product according to claim 2, wherein theratio of surfactant to polydimethylsiloxane is 9.5:0.5 and about 100% ofthe polydimethylsiloxane dispersed particles are between 1 and 9microns.
 9. A non-floss type interdental device according to claim 2,wherein the polydimethylsiloxane has a viscosity of 2.5 million cs andthe surfactant is a solid at room temperature.
 10. A non-floss typeinterdental delivery device according to claim 1, wherein the surfactantis selected from the group consisting of, flowable liquids of varyingviscosities, pastes, prills and cast solids.
 11. A non-floss typeinterdental device according to claim 1, wherein the ratio of surfactantto polydimethylsiloxane is 9:1 and about 90% of the polydimethylsiloxanedispersed particles are between 1 and 3 microns.
 12. A non-floss typeinterdental device according to claim 1, wherein the ratio of surfactantto polydimethylsiloxane is 2:1 and about 90% of the polydimethylsiloxanedispersed particles are between 1 and 3 microns.
 13. A non-floss typeinterdental device according to claim 1, wherein the silicone containsan active ingredient selected from the group consisting of, anti-plaque,anti-tartar, anti-gingivitis and anti-periodontitis active ingredients.14. A non-floss type interdental device according to claim 13, whereinthe silicone contains triclosan.
 15. A non-floss type interdental deviceaccording to claim 13, wherein the silicone contains the mixture ofessential oils comprising: thymol, eucalyptol, menthol and methylsalicylate.
 16. A non-floss type interdental device according to claim13, wherein the silicone contains stannous fluoride.
 17. A non-flosstype interdental device according to claim 13, wherein the siliconecontains chlorhexidine.
 18. A non-floss type interdental deviceaccording to claim 13, wherein the silicone contains metronidazole. 19.A non-floss type interdental device according to claim 1, wherein thedevice is for treating periodontal pockets.
 20. A non-floss typeinterdental device according to claim 19, wherein the device is a woodenstimulator containing tetracycline in said silicone.
 21. A non-flosstype interdental device according to claim 1, wherein the device is anelastomeric massager where the silicone contains one or moreantimicrobials selected from the group consisting of stannous fluoride,triclosan, chlorhexidine and metronidazole.
 22. A non-floss typeinterdental device to claim 1, wherein the device is an elastomericmassager and the silicone therein contains benzocaine.
 23. Aninterdental delivery device coating containing a high shear ULTRAMULSIONdispersion comprising a nonionic poloxamer surfactant andpolydimethylsiloxane insoluble in said surfactant wherein:a. saidpolydimethylsiloxane is oriented has the chemical composition (CH₃)₃SiO[SiO(CH₃)₂ ]_(n) Si(CH₃)₃, wherein n is a whole number; b. saidsurfactant has the chemical composition ##STR6## wherein x, y, and x'are whole numbers; c. the viscosity of the polydimethylsiloxane rangesfrom between about 100,000 and about 4 million cs; d. the particle sizeof most of the polydimethylsiloxane in the ULTRAMULSION dispersion isfrom between about 0.1 and about 10 microns; e. from between about 80%and 95% of said polydimethylsiloxane particles in the ULTRAMULSIONdispersion are from between about 1 and about 10 microns; f. thenonionic surfactant at is a polyoxyethylene-polyoxypropylene blockcopolymer having a molecular weight from between about 1,100 and about150,000; g. the ratio of surfactant to polydimethylsiloxane is frombetween about 400:1 and about 1:2; and h. the polydimethylsiloxanecontains one or more lipid suitable active ingredients.
 24. Aninterdental device according to claim 23, wherein the silicone is apolydimethylsiloxane uncoiled and oriented wherein the oxygen moietiesare generally oriented in a plane distinct from that of themethyl/moieties.
 25. A method of manufacturing interdental deliverydevices treated with an ULTRAMULSION dispersion said method comprising,heating a surfactant and a silicone mixture in a heated, stirred vesselsubstantially free from water, followed by subjecting said mixture tohigh shear dispersion and introducing said dispersion into saidinterdental delivery device by means of a vacuum loading; wherein:a. thesilicone is insoluble in said surfactant, has a viscosity greater thanabout 100,000 cs and up to about 50 million cs, and a particle size upto about 10 microns, b. the surfactant to silicone ratio in the highshear dispersion is from between about 400:1 and about 1:1; and thesurfactant has an orienting effect on the silicone, c. the silicone isoriented, exhibits enhanced substantivity to surfaces in the oral cavityand functions as a reservoir for one or more lipid soluble and lipiddispersible oral care active ingredients.
 26. A method according toclaim 25, wherein the heated vessel is provided with an inert head ofgas.
 27. A method according to claim 25, wherein said high sheardispersing means is fitted with a small orifice.
 28. A method accordingto claim 25 wherein said high shear dispersing means comprisesultrasonication means.
 29. A method according to claim 25, wherein thehigh shear dispersion is achieved with dispersing means selected fromthe group consisting of an IKA-WORKS DISPAX REACTOR fitted with at leastone superfine generator, a ROSS MODEL M.E. 100 2C fitted with a 20 meshscreen, and a ultrasonic MEDSONIC XL2010 fitted with 800-C flow cell and800 21CT 3/4 inch flanged horn.